In what civic leaders and elected officials called a game-changer and a new era for Milwaukee, former Sen. Herb Kohl announced the sale of the Milwaukee Bucks to two New York hedge-fund investors for $550 million, and said he and the new ownership team each will commit $100 million toward a new multipurpose arena.

The team's sale had been rumored for weeks, but what was not known until now was how much money for a new arena would be offered by Kohl, a lifelong philanthropist, and the new owners, who were introduced Wednesday afternoon at the BMO Harris Bradley Center as Marc Lasry and Wesley Edens.

"This is a major step forward in my goal in keeping the Bucks here," said Kohl, who bought the Bucks for $18 million in 1985 and has owned the team for 29 years.

The $550 million sale figure stunned many who follow sports transactions and must have brought smiles to the faces of NBA executives, given Milwaukee's small-market status.

In January, Forbes magazine, which compiles valuations of professional sports teams, said the Bucks were the least-valued team in the National Basketball Association at $405 million.

Nearly a year ago, the Sacramento Kings, in a larger market, were sold for $535 million.

Marc Marotta, chairman of the BMO Harris Bradley Center board of directors, heralded the news that Kohl had committed $100 million and Lasry and Edens had offered to provide at least $100 million more toward a new facility.

"This announcement provided new momentum for the project," Marotta said. "This is a huge, huge commitment for our city and the state of Wisconsin. It will present opportunities obviously for the future ... and it will help our community for years and years and decades to come."

'A dream come true'

Lasry told a large gathering at the Bradley Center that he and Edens "want to build a great team and a beautiful arena."

"We are looking forward to the experience of being an owner," Edens said. "We have a big vision for the Bucks," adding that fans deserve a winning team.

"For Wes and I, it really is a dream come true," said Lasry, who said he and his partner hoped to bring a championship to the city in the next five to 10 years.

Edens is the co-founder of the Fortress Investment Group LLC, based in New York, and a self-described basketball fan. According to federal Securities & Exchange Commission documents, the firm has $61.8 billion in assets under management. He is a graduate of Oregon State University.

Lasry is the chairman, CEO and co-founder of Avenue Capital Group. As of March 31, the firm had $13.6 billion in assets under management. Lasry is a native of Morocco who moved to the United States. He is a graduate of Clark University and holds a law degree from New York Law School.

Lasry ranks as one of the wealthiest Americans in the country, according to Forbes magazine. The magazine reported in 2013 that he had a net worth of $1.5 billion, good for a ranking of 352 on the list of the wealthiest 400 Americans.

Both said they intended to spend considerable time in Milwaukee assessing the team and how to move forward on a new arena.

Steve Greenberg, the Allen & Co. executive who handled the sale for Kohl, said Edens had been on his radar screen for some time as a possible owner. "In our world, we knew him and we knew his interest in sports," Greenberg said. "We reached out to Wes very early."

Greenberg said Lasry was known to him because he had explored buying another sports property. "Three weeks later, Wes said he and Marc wanted to work together," Greenberg said.

"They took the reins and whipped the horse," Greenberg said. "And they got out in front of the pack. They worked harder, longer and faster and they hit the bid."

Greenberg said there were nine interested parties in the Bucks, some of them potential local investors. He declined to name them.

An ownership transfer is subject to NBA approval. Kohl said he would be in New York on Thursday to introduce Edens and Lasry to league owners. He said he did not think a vote would be taken on the sale this week.

Kohl giving up full stake

Kohl's decision to transfer complete ownership of the team to Edens and Lasry came as somewhat of a surprise. Kohl has said for years he loves owning the team. In 2003, he nearly sold the team to former NBA superstar Michael Jordan, who later become owner of the Charlotte franchise. In the end, Kohl held onto his team.

The Bucks reached their peak of Kohl's tenure when they qualified for the Eastern Conference finals during the 2000-'01 season under coach George Karl, but they lost in seven games to Philadelphia.

Asked what made him change his mind about giving up total ownership of the team he has owned since 1985, Kohl was wistful and pragmatic.

"I wasn't going to live forever," Kohl said. "I approached a time in life when I had to think about approaching the idea of succession and then it was brought to a head the need for a new building and the fact that this is a project over several years. It doesn't get done in a short time. It came to me and it was very clear that the owners of the team over the next period of years should have a central role in the project. Not me, but them."

Team must stay, Kohl says

Kohl announced in December he was searching for additional investors to take the franchise into the future. He made a condition of a sale that the team would remain in Milwaukee.

Throughout the sale process, there had been consistent reports of possible local investors. Those potential investors included Mark Attanasio, principal owner of the Milwaukee Brewers; Craig Leipold of Racine, who is the owner of the NHL's Minnesota Wild; Jon Hammes of the Hammes Co.; and former Bucks star Junior Bridgeman, who has an ownership stake in the Sacramento Kings.

In the end, Kohl said he felt comfortable with Edens and Lasry and their commitment to Milwaukee.

"They were all over this from the very beginning," Kohl told the Journal Sentinel. "Very persuasive. Very attractive. Very successful. Ambitious. Right age. Good energy level."

"They wanted an NBA team. They see it as a good investment. An exciting investment. Something they might be good at."

Kohl said it helped that the two had the financial wherewithal to buy the team. Some potential owners have to finance them, he said.

"They have run organizations before," Kohl said.

In a statement issued by the NBA, Commissioner Adam Silver said Kohl had an "extraordinary impact on his home city of Milwaukee and the state of Wisconsin."

"His historic and unprecedented $100 million gift to the city of Milwaukee to secure the future of his franchise emphatically underscores his passion, commitment and generosity to his community."

One potential investor, who asked to remain anonymous because he had expressed interest in joining another investor group, said he was surprised Kohl and Allen & Co., which handled the sale, moved so quickly.

"It surprised me. I knew there were a couple of groups. But it moved very quickly," he said.

A source who is familiar with the sale of the team said some potential bidders offered less than $400 million for the team.

"Allen said don't even bother," the source said. "They only paid attention to a bid that started with the number 5."

Kohl likely could have sold his team for a far higher price had he allowed the team to move out of Milwaukee. He said, however, that Edens and Lasry shared "my love of the game and my commitment to keep the team in Milwaukee."

Charles F. Gardner of the Journal Sentinel staff contributed to this report.